PIC32MX420F032H-40I/ - 32-bit 40MHz MCU 32KB Flash USB-OTG
MPN: PIC32MX420F032H-40I/ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.4 | $6.40 |
| 10 | $5.85 | $58.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.1 | $4,100.00 |
PIC32MX420F032H-40I/ Overview
What is a PIC32MX microcontroller? PIC32MX is Microchip's mid-range 32-bit MCU family built on the MIPS32 M4K core. It bridges 8-bit PIC and 32-bit MIPS architectures for embedded systems, combining Harvard architecture, a 5-stage pipeline, single-cycle multiply, and a hardware divide unit with MIPS16e compression for up to 40% smaller code size. Within the MCU hierarchy, PIC32MX sits between 8-bit PIC MCUs and Cortex-M ARM-based MCUs, belonging to the broader category of 32-bit Flash microcontrollers used for general-purpose and USB-connected embedded designs.
Key features include 32 KB Flash, 8 KB RAM, four 16-bit timers, a 10-bit 1 Msps ADC with up to 16 channels, two comparators, two UART/SPI/I2C modules, and up to 53 user I/O pins. The device operates from 2.5 V to 3.6 V across an industrial -40 °C to +85 °C temperature range, and is RoHS compliant per the manufacturer datasheet. Compared with PIC32MX1/2/3xx devices, the MX4xx line adds the USB-OTG full-speed PHY and a dedicated DMA channel, which simplifies USB firmware by offloading packet movement from the CPU.
Typical applications include USB human-interface devices (HID), CDC virtual COM ports, embedded web servers, USB data loggers, industrial sensor interfaces, and graphics-enabled HMI panels that benefit from the parallel master port and enhanced PWM peripherals. Designers often pair it with Microchip's MPLAB Harmony framework, which provides ready-to-use USB stack, TCP/IP, and graphical libraries.
Design considerations include ensuring adequate decoupling near VDD/VUSB pins, using the on-chip 8 MHz FRC or an external crystal for USB accuracy, and following Microchip layout guidelines for the USB D+/D- lines. The -40I temperature grade suits industrial enclosures, while the -40V grade targets commercial environments; pick the variant matched to your worst-case ambient.
This page synthesizes distributor pricing, drop-in same-family alternatives, USB-OTG design notes, and a parameter comparison matrix that is not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC32MX420F032H-40I/ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC32MX420F032H-40I/ (same form factor and footprint) — differing in ADC, Operating Temperature, Package, USB, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC32MX320F032H-40I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.32 / Unit
View Datasheet →PIC32MX320F064HT-40I/MR
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.79 / Unit
View Datasheet →PIC32MX320F064HT-40I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.16 / Unit
View Datasheet →PIC32MX370F512HT-V/MR
✅ Drop-In✓ In Stock
$4.61 / Unit
View Datasheet →PIC32MX340F128H-80V/MR
✅ Drop-In✓ In Stock
$3.72 / Unit
View Datasheet →PIC32MX420F032H-40I/ Maximum Ratings & Electrical Characteristics
| Architecture | MIPS32 M4K |
| Core | 32-bit MIPS M4K |
| Maximum CPU Clock | 40 MHz |
| Performance | 66 DMIPS |
| Program Flash Memory | 32 KB (32K x 8) |
| Data SRAM | 8 KB |
| Supply Voltage | 2.5 V to 3.6 V |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| USB Interface | USB 2.0 On-The-Go (OTG) with on-chip PHY |
| ADC | 10-bit, up to 16 channels |
| Timers | 5 x 16-bit |
| UART/SPI/I2C Modules | 2 |
| Digital I/O Pins | 53 |
| Package | 64-pin VQFN (MR) 9 x 9 mm |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC32MX420F032H-40I/ Pin Configuration
| Pin 1 | RPB0/RD0 — Remappable I/O / ICD data line |
| Pin 2 | RPB1/RD1 — Remappable I/O |
| Pin 3 | RPB2/RD2 — Remappable I/O |
| Pin 4 | RPB3/RD3 — Remappable I/O |
| Pin 5 | VSS — Ground |
| Pin 6 | VDD — Positive supply 2.5-3.6 V |
| Pin 7 | RPB4/RD4 — Remappable I/O |
| Pin 8 | RPB5/RD5 — Remappable I/O |
| Pin 9 | RPB6/RD6 — Remappable I/O |
| Pin 10 | RPB7/RD7 — Remappable I/O |
| Pin 11 | VSS — Ground |
| Pin 12 | VDD — Positive supply 2.5-3.6 V |
| Pin 13 | RPB8/RD8 — Remappable I/O |
| Pin 14 | RPB9/RD9 — Remappable I/O |
| Pin 15 | RPB10/RD10 — Remappable I/O |
| Pin 16 | RPB11/RD11 — Remappable I/O |
| Pin 17 | VSS — Ground |
| Pin 18 | VDD — Positive supply 2.5-3.6 V |
| Pin 19 | RPB12/RD12 — Remappable I/O |
| Pin 20 | RPB13/RD13 — Remappable I/O |
| Pin 21 | RPB14/RD14 — Remappable I/O |
| Pin 22 | RPB15/RD15 — Remappable I/O |
| Pin 23 | VSS — Ground |
| Pin 24 | VDD — Positive supply 2.5-3.6 V |
| Pin 25 | RPC0/SDI1 — Remappable I/O / SPI1 data in |
| Pin 26 | RPC1/SDO1 — Remappable I/O / SPI1 data out |
| Pin 27 | RPC2/SDI2 — Remappable I/O / SPI2 data in |
| Pin 28 | RPC3/SDO2 — Remappable I/O / SPI2 data out |
| Pin 29 | RPC4/SCK1 — Remappable I/O / SPI1 clock |
| Pin 30 | RPC5/SCK2 — Remappable I/O / SPI2 clock |
| Pin 31 | VSS — Ground |
| Pin 32 | VDD — Positive supply 2.5-3.6 V |
| Pin 33 | D+ — USB D+ line |
| Pin 34 | D- — USB D- line |
| Pin 35 | VUSB — USB transceiver supply (3.3 V) |
| Pin 36 | VSS — Ground |
| Pin 37 | RPD0/OC1 — Remappable I/O / Output Compare 1 |
| Pin 38 | RPD1/OC2 — Remappable I/O / Output Compare 2 |
| Pin 39 | RPD2/OC3 — Remappable I/O / Output Compare 3 |
| Pin 40 | RPD3/OC4 — Remappable I/O / Output Compare 4 |
| Pin 41 | RPD4/OC5 — Remappable I/O / Output Compare 5 |
| Pin 42 | RPD5/RTCC — Remappable I/O / RTCC alarm output |
| Pin 43 | RPD6/SOSCO — Remappable I/O / Secondary oscillator out |
| Pin 44 | RPD7/SOSCI — Remappable I/O / Secondary oscillator in |
| Pin 45 | VSS — Ground |
| Pin 46 | VDD — Positive supply 2.5-3.6 V |
| Pin 47 | RPD8/OC6 — Remappable I/O / Output Compare 6 |
| Pin 48 | RPD9/OC7 — Remappable I/O / Output Compare 7 |
| Pin 49 | RPD10/IC1 — Remappable I/O / Input Capture 1 |
| Pin 50 | RPD11/IC2 — Remappable I/O / Input Capture 2 |
| Pin 51 | RPD12/IC3 — Remappable I/O / Input Capture 3 |
| Pin 52 | RPD13/IC4 — Remappable I/O / Input Capture 4 |
| Pin 53 | RPD14/IC5 — Remappable I/O / Input Capture 5 |
| Pin 54 | RPD15/OC8 — Remappable I/O / Output Compare 8 |
| Pin 55 | RPG6/SCK2A — Remappable I/O |
| Pin 56 | RPG7/SDO2A — Remappable I/O |
| Pin 57 | RPG8/SDI2A — Remappable I/O |
| Pin 58 | RPG9/SS2A — Remappable I/O |
| Pin 59 | VSS — Ground |
| Pin 60 | VDD — Positive supply 2.5-3.6 V |
| Pin 61 | AN0 — Analog input 0 |
| Pin 62 | AN1 — Analog input 1 |
| Pin 63 | OSC1 — Crystal oscillator input |
| Pin 64 | OSC2 — Crystal oscillator output |
Typical Applications
PIC32MX420F032H-40I/ is suitable for 6 applications: USB Human Interface Device (HID), USB CDC Virtual COM Port, USB Data Logger, Industrial Sensor Interface, Embedded Web Server (Light HTTP/HTTPS), HMI / Graphics-Enabled Control Panel.
USB Human Interface Device (HID)
The PIC32MX420F032H-40I/ is a strong fit for USB HID peripherals such as keyboards, mice, gamepads, and custom control surfaces. Its integrated USB 2.0 On-The-Go controller with on-chip PHY eliminates the need for an external transceiver, while the dedicated DMA channel for USB traffic keeps packet movement off the CPU so the MIPS M4K core can focus on HID report generation and switch debouncing. With 32 KB Flash, the device comfortably fits a USB HID class driver plus a typical device descriptor and report map. The 40 MHz core plus 66 DMIPS gives sub-millisecond report latency even when the HID stack also services a small OLED or LED indicator.
Recommended
USB CDC Virtual COM Port
For USB-to-UART bridges and virtual COM port designs, the PIC32MX420F032H-40I/ offers a tightly integrated solution. The USB-OTG full-speed PHY plus two on-chip UART modules let one UART pair with USB for CDC bridging while the second serves an external sensor. With 8 KB of SRAM, the device can hold USB CDC class driver state plus a 256-byte ring buffer for incoming bytes without external memory. The 40 MHz core easily handles 921600 baud line rates with negligible CPU loading, and the 2.5-3.6 V supply matches most RS-232 level-shifter or RS-485 transceiver rails in industrial designs.
Recommended
USB Data Logger
The PIC32MX420F032H-40I/ is well matched to USB-connected data loggers such as temperature, humidity, or vibration recorders. The 10-bit ADC with up to 16 channels handles multiple analog sensors, while the 8 KB SRAM can buffer several seconds of samples before USB upload. The integrated USB-OTG PHY allows direct connection to a host PC as a Mass Storage Device (MSD) so log files can be dropped onto the host file system without a custom driver. Industrial -40 to +85 °C temperature support and RoHS compliance let these loggers be deployed in factory floors or outdoor enclosures.
Recommended
Industrial Sensor Interface
For 4-20 mA loop-powered sensor interfaces and industrial controllers, the PIC32MX420F032H-40I/ offers the right mix of analog and digital peripherals. The 10-bit ADC handles multiple sensor inputs while the 5 x 16-bit timers drive PWM outputs for actuator control. USB-OTG supports configuration via CDC class without a separate programming header, simplifying field installation. The 2.5-3.6 V supply and -40 to +85 °C industrial temperature grade match the harsh requirements of factory automation environments. The 53 user I/O pins support multi-channel sensor matrices with room for status LEDs and a small HMI keypad.
Recommended
Embedded Web Server (Light HTTP/HTTPS)
For small embedded HTTP servers controlling a smart sensor or home-automation node, the PIC32MX420F032H-40I/ can host a minimal TCP/IP stack alongside a USB stack, though with 32 KB Flash the embedded web role is limited to configuration pages rather than rich HTML. The 40 MHz MIPS M4K core and 8 KB RAM are sufficient for a Microchip Harmony TCP/IP lite profile serving a few static pages and JSON status endpoints. The on-chip USB-OTG allows the device to also appear as a CDC configuration port simultaneously, eliminating the need for a separate serial interface.
Recommended
HMI / Graphics-Enabled Control Panel
The PIC32MX420F032H-40I/ suits low-resolution HMI panels using its parallel master port (PMP) interface to drive small TFT or OLED displays up to 4-inch in QVGA mode. The enhanced PWM outputs can dim the backlight, while the USB-OTG allows firmware updates from a USB stick or a host PC. With 32 KB Flash the device handles small graphical libraries and a state machine but is best for icon-based menus rather than full graphical designers. The 53 I/O pins support a 4x4 keypad, multiple status LEDs, and rotary encoder inputs in parallel with the display interface.
Recommended
Recommended Products Summary
Engineering reference data for PIC32MX420F032H-40I/ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC32MX320F032H-40I/PT | PIC32MX320F064HT-40I/MR | PIC32MX370F512HT-V/MR | PIC32MX340F128H-80V/MR |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | VQFN-64 (MR) | TQFP-64 (PT) | VQFN-64 (MR) | VQFN-64 (MR) | VQFN-64 (MR) |
| Architecture | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K | MIPS32 M4K |
| Maximum CPU Clock | 40 MHz | 40 MHz | 40 MHz | 50 MHz | 80 MHz |
| Flash Memory | 32 KB | 32 KB | 64 KB | 512 KB | 128 KB |
| SRAM | 8 KB | 8 KB | 16 KB | 128 KB | 32 KB |
| USB OTG | Yes (integrated PHY) | Yes (integrated PHY) | Yes (integrated PHY) | Yes (integrated PHY) | Yes (integrated PHY) |
| Supply Voltage | 2.5 V to 3.6 V | 2.5 V to 3.6 V | 2.5 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V |
Key Differentiators
- Integrated USB-OTG PHY in a VQFN-64 package (vs PIC32MX320F032H-40I/PT)
- 32 KB Flash / 8 KB RAM at 40 MHz is the optimum cost point for USB HID/CDC (vs PIC32MX370F512HT-V/MR)
- Industrial -40 to +85 °C temperature range included by default (vs PIC32MX340F128H-80V/MR)
Design Notes
Place one 0.1 µF decoupling capacitor as close as possible to each VDD/VSS pair on the PIC32MX420F032H-40I/. Add a bulk 10 µF tantalum or ceramic capacitor near the device. For USB applications, also decouple VUSB (pin 35) with a 0.1 µF + 4.7 µF combination to keep the internal USB LDO regulator stable. Estimated: at 40 MHz full-speed USB operation, core current draw is around 30 mA, and USB pull-up adds ~1 mA, so budget ~50 mA from a 3.3 V regulator with adequate headroom.
Keep USB D+ and D- lines as short as possible, with matched length and 90 Ω differential impedance per USB 2.0 full-speed requirements. Avoid routing them near noisy switching nodes or oscillators. Place the 12 MHz or 8 MHz crystal close to OSC1/OSC2 (pins 63-64) with guard traces to ground, as the USB PLL multiplies this reference for the 48 MHz USB clock. Estimated: signal integrity at full-speed USB tolerates ~4 inches of matched pair on FR4 with proper stack-up.
A common pitfall with the PIC32MX420F032H-40I/ is failing to set the correct configuration bits before USB enumeration: CFGCON.IOLOCK must be unlocked to use remappable peripherals, and CFGCON.USBIDEN must be configured for OTG host vs device role. Also, ensure the device ID protection bits are not accidentally set, which would brick debug access. Refer to Section 7 of the family datasheet (61143H) for proper fuse programming order.
The VQFN-64 (MR) package has an exposed thermal pad that must be soldered to a copper pour on the PCB for proper heat dissipation. Estimated: at full CPU (40 MHz) and all peripherals active, power dissipation is approximately 240 mW, keeping junction rise below 25 °C above ambient with the recommended thermal pad layout. For sealed enclosures without airflow, derate the operating frequency or add a small heatsink footprint to the thermal pad area.
Compliance Information
RoHS compliance and lead-free status confirmed per Microchip product page. Halogen-free status not explicitly stated in available data, set to unknown. AEC-Q100 not applicable - this is an industrial-grade MCU, not an automotive-qualified part.
